I learnd about keeeb in it's early days around 2013 and love it since then. The usage is not only simple but also great fun - that's how to get everyone of your team involved to collect and share knowledge!
The ease of use and support ov various file formats are the biggest pros in my eyes.
Until now I did not found any Cons worth to consider :-)
It is easy to use and set up. We just needed to install the Keeeb extension for our browser and MS Office and we were done. The design and user interface is pretty straight forward and the Keeeb team gave us a personal onboarding which was great. You still need to get in contact with them to get your onw account. But they are fast to answer any mails.